This application claims the entire benefit of Japanese Patent Application Number 2009-056876 filed on Mar. 10, 2009, the entirety of which is incorporated by reference.
1. Field of the Invention
The present invention relates to a sander equipped with a clamp device for a sanding sheet.
2. Description of Related Art
Various techniques for sanders have been disclosed in the art for clamping a sanding sheet with respect to a sander. For example, Japanese Utility Model Publication No. S53-020796 discloses a paper clamping device for a sander. The paper clamping device comprises a metal clamp 15 provided on a plate 8 through a spring 20 so as to be urged in a closed direction by the resilient force of the spring 20, and an elastic material 21 positioned between the metal clamp 15 and a paper-hanging plate 14 protruding upward from an end portion of a sanding plate 9. A paper 13 is clamped between the elastic material 21 and the metal clamp 15, and when the elastic material 21 undergoes a compressive deformation, the paper 13 is further pulled and tensed in accordance with the amount of compressive deformation.
However, according to the aforementioned paper clamping device disclosed in Japanese Utility Model Publication No. S53-020796, the metal clamp 15 is configured such that an operating plate member 17 is rotatable around a pivot axis 19 which is transversely mounted on the sanding plate 9 via a bracket 18. For this reason, the operating plate member 17 has to extend upward from the sanding plate 9. This may disadvantageously cause an operator to operate the operating plate member 17 by mistake during the sanding operation. However, reducing the length of the operating plate member 17 would result in an increase in the operating load for the operating plate member 17, so that the operator is required a great deal of effort for a single-handed operation and thus the setting operation becomes arduous. Especially, if the operator releases his hand from the operating plate member 17, the operating plate member 17 returns to the clamping position by the resilient action of the spring 20. Therefore, upon attachment and/or removal of the paper 13, the operator is always required to hold the operating plate member 17 in the unclamping position. This results in deterioration of the operability.
In view of the above disadvantages, the present invention seeks to provide a sander which can reduce the operating load without decreasing reliability for clamping a sanding sheet as well as ease the setting operation.
The present invention has been made in an attempt to eliminate the above disadvantages, and illustrative, non-limiting embodiments of the present invention overcome the above disadvantages and other disadvantages not described above.